Hirschmann PAT DS 85/0002 - 8 Load Theory; 9 A2 B Problem

Service Manual DS 85
© Hirschmann Rev.G 10/05/15 190166_G.DOCXG
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8 LOAD THEORY
Please note that the load displayed by the LMI is not a direct measurement, but a calculated value
that is based on a lot of factors. Outside of the measured values (sensors), those include:
 Operator settings such as:
o Operating mode/configuration
o Parts of Line/Reeving
 Rigging parts such as:
 Hook block weight
 Sling weights, etc.
 Tip height (length of load line used)
 Boom weights
Before checking the system for a load reading problem, make sure all of the above has been
ruled out. When you still feel, the system is reading a sensor wrong and thus displaying an
incorrect load, use the following:
Use the above sections and the sensor signal display screen to check the following:
boom length reading
angle transducer reading
pressure transducer readings
If all are correct, use the zero setting and calibration screens to zero pressure transducers, calibrate
angle and length. If you still have a problem, replace pressure transducer block.
9 A2B PROBLEM
 CHECK FOR ANTI-TWO BLOCK CONDITION
Are the control levers locked out and is the crane in an anti-two block condition?
YES, Lower the hook block and/or headache ball to correct the two-block condition. If two (2)
hoists are in use, both hooks must be lowered.
 CHECK THE LED’S ON THE RADIO ANTI-TWO BLOCK RECEIVER BOX
1. ‘POWER’ (Red)
This Red LED lights to indicate power to the system.
2. ‘ONLINE’ (Green)
Indicates the status of communication between main hoist A2B transmitter
and the receiver. Failure of the communication link will turn off the Green
LED and turn off the output to the lockout relay.
3. ‘LOW BATT’ (Yellow)
Indicates weak batteries specific to channel 1 or 2 when Yellow LED lights.
4. ‘INFO’ (Red)
Indicates a two-block condition of the main hoist. The Red LED will light
when the load-handling device has lifted the A2B weight.